To meet the requirement of various different occasions, environments and demands, except for fixed type installation, it is essential to which outdoor lighting fixture shall be made available for portable and installation (fixed) at any place as desired.
Most of conventional portable type outdoor lamps are of clamp type, i.e. their structure comprises lamp head, lamp stem, clam holder or hanger for fixed with clamp holder or hanging up with hanger.
As there are wide variety of bulbs available for use, such as white bulb or halogen lamp; in addition, power specification includes AC, DC or car power supply. In short, outdoor lamps are extended to a wider variety of occasions.
If a conventional lamp holder is intended for the use in garden, camping, roadside or car repair, etc., it is often regretted for failure of use due to the problem of fixing position or angle.